The treatment of yarn in package form may involve washing, bleaching, dyeing, rinsing or other liquid treatment. The yarn is typically wound on dye tubes as yarn packages and placed on a series of spindles or other core members within a treatment chamber. The yarn treating liquid is circulated into the treatment chamber and through the packages of yarn at elevated temperatures and pressures. The heated liquid under pressure penetrates the package and the individual strands of yarn or fibers fully or to a predetermined depth for special effects. The treating liquid is typically forced from the spindle or core member into the inside of the tube outwardly through the yarn, and in some systems the treating liquid is forced from outside the package inward through the package into the core member.
A problem with previous package dyeing systems is that it has not been practically feasible to vary the amount of treatment liquor for optimum usage with loads of yarn varying from a standard capacity of the system. This use of oversized equipment for small loads is both expensive and environmentally unsound because of the need to fill the kiers with the same amount of liquor as for full sized loads.
In other types of textile dyeing systems, for example dye becks for treating lengths rather than packages of textile material, where relatively large dye becks are standard in the art and are designed to handle several hundred yards of material bunched in rope form, conversion systems, such as disclosed in U.S. Pat. No. 3,635,053, have been developed for changing the capacities of such large dye becks by employing a number of relatively small dye becks constructed and designed to be fitted into the standard large dye beck in a side-by-side relation so that separate dyeing operations can be carried out in each of the smaller dye becks simultaneously. However, a satisfactory practical method and apparatus for selectively varying the capacities in package dyeing systems to adjust to loads varying from a standard load are not known.